Hair clippers require drive systems that maintain linear motion of a reciprocating blade. To guide the reciprocating blade parallel to the stationary blade, the drive systems require precision tolerances. They may use a spring to guide the reciprocating blade in a near-linear path, but spring tolerances are difficult to sustain in manufacturing. As a result, the spring often requires adjustment at the factory assembly line to properly align the reciprocating blade with respect to the stationary blade.
Some drive systems have a guide channel formed in a thick section of the stationary blade, but the thick section is distanced from the cutting load, making the reciprocating blade guiding susceptible to binding. Moreover, sometimes an external feature (such as a cam follower flange) reciprocates outside of the housing, which is an aesthetic disadvantage, or a guide is molded on a housing that if excessively worn can require replacement of the entire housing and a more complex service repair procedure.
Another drive system design has a guide for guiding the reciprocating blade. The guide attaches to the perimeter of the clipper housings. Since a taper adjustment feature is provided on many hair clippers, this type of guide piece introduces more parts and additional manufacturing tolerances to sustain in production for the taper lever adjustment.
In addition, removal and re-assembly of the blade set can be awkward if the user in the field has to depress the spring and cam follower downward while inserting the reciprocating blade and fastening the fixed blade. Thus there is a need for improved drive systems for hair clippers.
Accordingly, one object of this invention is to provide new and improved hair clippers.
Another object is to provide new and improved drive systems for hair clippers driven by a rotary motor or a vibrator motor.